Electric battery of the leclanche type



Oct. 9, 1928. v 1,687,051

- G. N. ANTONOFF I ELECTRIC BATTERY OF THE'LECLANCHE TYPE Filed may 26; 1924 2 SheetS-Sheet 1 Oct. 9, 192a s. N. ANTONOFF ELECTRIC BATTERY -OF THE LECLANCHE 'IYYE Filed m 26, 1924 z-smus-snu 't 2 ill Patented Oct. 9, .1928.

U'N'l TED ST A res PATENr OFFICE.

GEORGE NICHOLAYEVIGH ANTONQFE, or Lennon, ENGLANR, Assicnon TO am'rfrnnvir ATKINSON ADAM, or LONDON, ENGLAND.

ELECTRIC BATTERY or run LncLANc it TYPE.

Application filed May 26, 1924, Serial No.

This invention relates to Leclancli cells in which zinc is used as the source of energy,

and carbon is used for the positive pole wIth manganese dioxide .as the depolarizer. In my British Patent No. 128,316 I have shown that the apparent density of the depolarizer is related to the internal re sistance and how for given materials and conditions of working the best region of apparent density for output can be found. I have now found that certain other factors affect the result and also the obtain ng of desired qualities of such cells, such as long life and maintenance of potential, economy of materials and space occupied for a given output. It has long been believed that vent-ilation of the depolarizer was advantageous, but although many proposals have been made to'secure this, itis the common practice now where ventilation is used to provide a simple tubular ventv through theseal'ng material which closes the zinc case so that the inside of the cell is in communication with the atmosphere through it while liquid is prevented from coming out. The zinc case is itself in practice enclosed in an internally waxed cardboard or other liquidtight enclosure.

Now I have found that ventilation plays a further partthan has been hitherto under: stood, and for this to be effective, first it is necessary for the exterioras well as the interior of the zinccase to beventilated. Second, the jelly or like layer which is employed between the depolorizer and the: zinc case should be produced in such a way as will avo'td any liquefying and washing away or change of the depolarizer mass or the surface thereof, as is liable to occur when the unjellified liquid containing starch is poured or otherwise introduced into the space between the depolarizer and thezinc case and the starch subse uently jellitied. Such procedure is unsatis act-ory with the low density depolarizers which I employ. I

As far as I am aware no prior disclosure describes an electrolyte formation which will obtain the benefit arising from appropriate ventilation as described below. Ventilation suspended 716,052; and in Great Britain June a, 19.23.

efl'ective'iby such an electrolyte, that is to commencementof theworking of the cell but may then. beof a gelatinous character,

but during the effective life of the cell must change to a more porous character, becom- 19g, Say, of the texture-eta cheese without llquefaction.

This invention in brief consists in an electric cell of the L'ecl-anchtype having say one which" may not be porous atthe mixture gelatinous yet firm and substantially non-porous at the time of makingbut turning to a firm porous mass of the consistency of cheese withoutliquefaction.

In the accompanying drawings Figure 5 represents part of a modification in which thesealing does not extend'over' the zinc container andthe outer casing, the cell being first sealed'and'then inesrted into the casing.

Figure 6 represents a modified fo'rm of Figure 5 with the addition ofa hole in the base of the zinc container a Figure 7 illustrates part of an improved cell of th.e,immunetype sometimes known as the inert type, that is to say-,acel-lwhich has a dry electrolyte which upon addition of water assumes the desired-consitency, thus becoming active for the purpose of operation as aso-called dry battery. V

In carrying this invention into effect in one form by way of exam-pleas appliedto a cell of 2% X 2 X 5 Itake a zinc case Figure 1 is a sectional elevation of a: cell Figure 3' shows separately the zinc coni a preferably of square tubular form and about 0.5 mm. thick or even less. The case should be sufficiently thck as not to become eaten away by the working of the cell for a considerable part of its life, say for the first half, but it is no detriment if it is suificiently thin that after this it becomes porous and indeed this assists ventilation. This case either has a zinc bottom I) covered with case the best economy in material and space is achieved. The edges of the outerbox 0 project above the zinc case a and the zinc is perforated near the top at f so as to permit of external and internal ventilation of the zinc case, namely ventilation from the slight space outside the zinc case into the inside thereof.

Although this form of external and in ternal ventilationthat is, from the outside of the zinc to the inside-may be used by itself by way of perforations, such as those marked f, or by Way of the single perforation 8 in the bottom of the cell referred to below, or by way of both 7 and s it is more beneficial to provide in addition a vent in the top of the cell, such as 0, described later.

The circulation permitted. by way of a vent can be obtained whether the vent is formed at the top or at the bottom of the cell. I prefer the former for practical reasons because if at the bottom unless suitably trapped the cell may exude liquid during the course of its operation.

In order to minimize or prevent leakage of liquid in appreciable quantities during the working of the cell which, for example, might hinder ventilation by closing the passages f, it is preferred to use only a limited quantity of liquid in the manufacture of the cell. In any particular construction should it be found that liquid is likely to become free it is preferred to provide a space indicated by d in Figure 1 between the bottom of the zinc and the cardboard case so that this can receive the liquid.

In any case the outer container should be moisture-retaining, so that even after the .Zinc has become perforated by the action of the cell external leakage is outer case.

The ventilating perforations f may be in the form of holes or preferably slots, for example as shown clearly in Figure 3.

prevented by the The depolarizer is made by moulding under pressure around a central carbon pole in the usual way, but the pressure of moulding should be such as will give to the compressed mass or dolly an apparent density between about 1.3 and 1.8 and preferably about 1.5 By apparent density 1 mean the ratio. of the mass of the mixture of manganese dioxid'e and graphite (dry and without salts) in grammes to the volume to which it is com= pressed in c. c. (excluding the carbon rod). The actual pressure varies with the materials used in the mixture mass, i. e. the character and gradeof the graphite and manganese dioxide and the content of liquid. The proportions of these are preferably 8 parts by weight of manganese dioxide to 2 parts of graphite, say Acheson B. B. 1, and 1 part of a solution containing about 5 per cent zinc chloride, 22 per cent ammonium chloride and 73 per cent water. I e

The dolly or depolarizer 9 thus formed with the carbon pole h is then wrapped in an open fabric such as muslin and has suit able spacing pieces 2' tied on externally. It is then placed centrally into the zinc case a with its insulated bottom, into which has been placed the required amount of the above solution containing about 3 to 5 per cent of a starch gel and preferably with 15 per cent to 20 per cent ungelatinized starch granules suspended in it. The dolly thus displaces the filling into an annulus surrounding it. The zinc case a is then heated to convert the remainder of the starch into gel. form, the free surface 70 of the gel being a little lower than the height of the depolarizer.

This mixture when made is substantially of a gelatinous nature but changes after a period to a spongy consistency of the nature of cheese, becoming firm yet porous. It does not liquefy during the working of the cell.

A sli ht layer of paraffin wax Z is then introduced on the top of the filling to seal the latter more or less. A perforated ring of celluloid or the like on is then placed on the top of the dolly near its edge and a cardboard washer a is placed on this ring extendingto and closing the zinc case a above the perforations f. The cardboard washer carries one or more tubular vents of glass 0 of suitable size, say 4 mm. diameter. The zinc case a is then placed into the cardboard outer case 6. The sealing mixture p of the cell. preferably bitumen and a filling agent, is

then introduced to fill up to the edge of the cardboard outer case and the edges of the vent or vents; The cell is thuscompleted, connections 9 and r having been made to the carbon and zinc previously.

Owing to the perforations 7" in the zinc case and in the celluloid ring 012, the outer surface of the zinc caseis in free communication with the top of $1}? dolly ,9.

Instead of carryingthe zinc case into the top seal some cases provision may be made for its being otherwise held in place and located 'in relation to the carbon and the case' may extend as high as the outer container and be sealed before insertion into the contamer as indlcated, for instance, in Figure 5.

The exterior of the zinc in this'case is venventilation be employed or not (and if ventilated by the comparative looseness of fit in. the container, the interior of the cell being open to atmosphere through the vent 0.

Another form of this class of construction is indicated in Figure 6 in which a hole 8 is provided in the base of the z nc container 0 leading from the inside to the outside of the zinc. In this form the bitumen or like sealing may extend over the top of the zinc case as in Figure 1 or not. I

A hole inthis position may also provided in a cell constructed asshown in Figure 1.

In preparing an improved cell of the socalled immune class, I only incorporate about half the salts required to form the electrolyte in the dolly and the otherhalf I thoroughly dry and mix with thoroughly driedgelatinized starch preferably of tapioca or the like and fill this powder into the annulus between the dolly and the zinc case, completing the cell. 1

' A layer of muslin or the like is provided to prevent the dry particles from falling out of the annulus during transport.

The zinc case maycontain the same slots.

which in this case are covered with a layer of unabsorbent cotton wool or the like which prevents water from passing into the outside of the zinc case.

Alternatively. a hole in the bottom of the zinc case is made and a layer ofunabsorbent cotton wool sealed 1nto it so as to prevent leakage of the liquid. I

Another form of cell of this character is I shown in Figure 7, the various parts of it may be cut square and terminate flush with A the washer n. In the latter case the space outside the: zinc case is filled with water and normal,

must be emptied afterwards. Care should be taken that the water is not heldthere by capillary forces.

'As in the-former case the perforations 7 may be in the nature of holes or slots in-one ortwo rows or a combination of holes and slots. In some cases theyneed not be provided.

A cell-thus constructed does not deteriorate on keeping over long periods,evenin quantity of water required it becomes active and gives the cell a life; not'shorter than" the In the case of the immune cell, whether p I .Grams Ammonium chloride; Tapioca. or the like 50 I have made a number of experiments and have found-thatif less tapioca or the like, is used there is a tendency for the water on addition to wash out the depolarizer, particularly if it be made under a comparatively low pressure.- If :more tapioca or the like is used the mass is not sufi iciently permeable.

to water so that the water does not atleast 1 for, some considerable time reach the bottom of the cell, the soaking of the starch on the way preventing it. I

If desired in any of the forms in place of forming holes or slots. I

Ventilation inside the cell may be ventilation inside the dolly ordepolarizer mass or ventilation between the external surface of the dolly and the internal surface of the ZlIlC. I

In place of dried gelatinized starch for the immunecell referred to above other materials with which there is no liquefaction can be employed, for example natural forms of starch. I

Tragacanth may also be used butin that case in order to enable the water to percolate throughout the mass of' the tragacanth agreater quantity of salts is required than with gelatinized starch.

Cells as described above may be made of any suitable size and shape, for example the ordinary size as used for telephone work or smaller sizes such as are employed for torch lights orpocket lamps."

Other examples of electrolyte mixtures which are gelatinous yet firm, substantially non-porous at the time of making but turn-' ing to a firm porous mass of the consistency of cheese without liquefaction during the action of the cell are as follows Per cent (up to about 30 C.) Agar-agar 3.5 Rice 12.0 Arrowroot 13.0 Maize" A 13.0 Wheat 12.0

natural form of starch. I

By natural starch is meant varieties of starch which swell or jellify on being brought into contact with .cold water, for

example tapioca and gum tragacanth as distinct from potato, rice and wheat starches.

Having now described my invention what I claim as new and desire to secure by Letters Patent is 1. An electric cell of the Leclanch type with an outer moisture-retaining case pro vided with free ventilation for the zinc electrode externally as well as internally and with an electrolyte mixture gelatinous yet firm and substantially non-porous at the time of making but turning to a firm porous mass of the consistency. of cheese without liquefication.

2. A cell as claimed in claim 1, in which the apparent density of the depolarizer mass lies in the region of 1.3 to 1.8 and preferably about 1.5.

3. A cell as claimed in claimv 1 in which ventilation is effected by establishing a com munication between the inside and outside of the zinc case by means of slots near the top of the case and slots near the bottom of the case.

1. .An electric cell as claimed in claim 1 with'communication between the inside and the outside of the zinc case and a vent leading from the inside to atmosphere.

5. A cell as claimed in claim lwith slots near the top of the zinc case, slots near the bottom of the zinc case and a vent leading from the inside of the zinc case near the top to the atmosphere.

6. A cell as claimed in. claim 1 in which ventilation is effected byestablishing a com munication between the outside and inside oft-he zinc case near thetop and near the bpttom of the case, preferably by means .O sets.

8. A cell as claimed in claim 1, in which ventilation is effected by establishing a communication between the inside and outside of the Zinc case by means of slots near the top thereof, and also by means of slots near the bottom thereof.

9. A cell as claimed in claim 1, in which ventilation is effected by establishing a communication between the inside and outside of the zinc case near the top .and near the bottom thereof, the connection at the top being free for the passage of gases, that is unobstructed by any obstructing material.

10. A cell as claimed in claim 1, with slots near the bottom of the zinc case and a vent leading from the inside of the zinc case near the top to the atmosphere. p i

11. A cell as claimed inclaim 1, in which ventilation is effected by establishing a communication between the outside and inside of the zinc case near the bottom of the case.

12. cell as claimed in claim 1 inwhich ventilation is effected by establishing a communication between the outside and inside of the zinc case by means of slotsnear the bottom of the case.

13. An electric cell of the Leclanch type with an outer moisture retaining case, a zinc-tubular electrode, provided with communications for the passage ofgases from the inside to. the outside of the electrode near the top and near the bottom of the electrode, a depolarizer mass, a carbon core, an

electrolyte mixture gelatinous yet but firm,

substantially non-porous at the time of making but turning to a firm porousmass of the consistency of cheese without liquefaction and containing at the time of making salts for the electrolyte, together with means for sealing the top of the cell.

14:. A method of-forming a dry cell which includes the steps of preparing a nearly liquid starch gel of low starch content suspending in this gel starch granules and completing the jellification of the mixtureby heat.

15. An electric cell of the Leclanch type with an outer moisture retaining case provided' with vents between the external atmosphere and the interior of the cell and vents between the zinc electrode and. the interior of, the cell together with an electrolyte mixture gelatinous yet firm and substantially nonporous at the time of .making but turning to a firm porous mass of the consistency of cheese without liquefaction. I

' 16. In combination, a zinc casing, adepolarizer mass within said. Zinc casing with a gap between the external periphery ot the mass and the 'interial periphery of the easing, a liquid starch gel of low starch content in said gap and ungelatinized starch granules suspended in said starch gel.

17 An electric cell of the Leclanch type vithan outer moisture-retaining case a zinc tubular electrode provided with communications for the passage of gases from the inside to the outside of the electrode near the 1 bottom of the electrode, a depolarizer mass,

a carbon core, an electrolyte mixture gelatinized yet firm substantially non-porous at the time of making but turning to a firm porous mass of the consistency of cheese without liquefaction and containing at the time of making slots for the electrolyte together with means for sealing the top of the ture of tapioca and finely divided dry salts. 20. A cell of the immune type in which the space between the depolarizer and the ture of starch and dry salts and the cell is sealed from the atmosphere. until it is required to be used. I

22. A cell of the immune type in which a mixture of starch and dry salts are employed, the proportion between these substances being so chosen that the water when added does not wash away the depolarizer yet reaches the bottom of the cell.

23. cell of the immune type containing the following, substances in about the proportions specified, namely about 100 parts by weight of ammonium chloride to about 50 parts by weight of tapioca.

In testimony whereof I have signed my name to this, specification.

GEORGE NICHOLAYEVICH ANTONOFF. 

